1. Field of the Invention
The present invention relates generally to a radiator/condenser pin assembly for an automobile.
2. Discussion of the Related Art
A radiator/condenser, in its assembled form, is held in place within an automobile's engine compartment by radiator/condenser pins. These pins are typically positioned in a vertical fashion near the (a) left-hand side of the top edge, (b) the left-hand side of the bottom edge, (c) the right-hand side of the top edge, and (d) the right-hand side of the bottom edge. The pins are usually manufactured from a plastic resin or a solid piece of metal.
Designs utilizing a plastic resin are problematic, however. Many jurisdictions have strict recycling laws regarding automobiles that are out of commission. In jurisdictions where an automobile's radiator/condenser must be recycled for raw materials, radiators/condensers having plastics resin pins must first have the plastic resin pins manually removed before the radiator/condenser can be recycled, resulting in an extra recycling expense.
Also, pins formed of a plastic resin are typically not as strong as pins formed of a metal. Recent trends within the automobile industry are toward enhancing ease of assembly. In the case of air conditioning units for automobiles, a condenser, a radiator, and receiver tanks are routinely combined together to form a single module. When multiple parts are combined together to form a module, the weight of the module often becomes quite heavy. However, in a given application, plastic resin pins can be insufficient to support the weight of the module.
Other applications in the art utilize radiator/condenser pins formed of a solid piece of metal. This solid piece of metal is typically formed via a cold forging process or via a machining process from a solid piece of metal. However, use of a solid piece of metal, such as aluminum, can add great expense to the cost of the pin. Also, the solid piece of metal adds a large amount of extra weight to the automobile, adversely affecting the automobile's fuel efficiency. In either case, if either a cold forging process or machining process is utilized, the pin cannot be formed from a cladded material. Accordingly, an additional process of applying brazing paste or a brazing sheet to the part prior to a brazing process is required.
For applications utilizing a pin formed of a single piece of metal, the shape of the pin is usually carved from a larger piece of material via a machining process, which can be a complicated and time-intensive process. Also, when solid pins are utilized, the material utilized to manufacture solid pins cannot be pre-coated with a cladding material to secure the solid pins to the radiator/condenser, because a cladding material typically cannot be used with a solid piece of metal material, and can only be used with sheet metal. Moreover, the solid pin typically affects the quality of the part when assembled onto a larger component. After the entire radiator/condenser assembly is assembled, the assembly is put through a brazing furnace to melt the clad material, thus brazing together individual components of the radiator/condenser assembly via the brazing process. In the brazing process, heat is applied to the entire radiator/condenser, with the objective of melting only the clad material and not the base material. If a certain area being brazed has a greater thickness than the rest of the radiator/condenser, that specific location takes longer time to heat up. Also, the extra mass requires extra heat to become hot enough to reach the material melt temperature. Conversely, if a certain area being brazed is thinner, then that particular location takes less time to reach the optimum temperature to melt the clad material. Since it takes less time to heat up lower mass areas, there is a potential to overheat the section, potentially melting not only the clad material but also the base material, resulting in destruction of the section during the brazing process.
Accordingly, when solid pins are utilized, extra energy must be expended during the brazing process. Since solid pins are typically thicker than the remainder of the radiator/condenser, more heat must be added to the entire assembly to ensure the radiator/condenser pins are properly brazed. As a result, more cost is expended to maintain higher furnace temperature. Also, the radiator/condenser assembly is typically on a conveyor belt during this brazing process and the furnace typically is heated to a set temperature. To ensure the solid pins are properly brazed, the speed of the conveyor must be slowed. As a consequence, the time required to properly braze the assembly is increased, resulting in a lower throughput than would be required if the solid pins had thicknesses similar to the rest of the radiator/condenser assemblies. Such solid pin assemblies are also deficient because, due to their solid designs, they cannot simultaneously serve as both a radiator/condenser pin and an end cap for a radiator/condenser manifold. End caps are caps that attach to both ends of a radiator/condenser manifold, since radiator/condenser manifolds are typically hollow pieces-similar to pipes.
Furthermore, designs in the current art provide only one brazing surface for brazing a radiator/condenser pin to a radiator/condenser header. FIG. 6 illustrates a pin 600 brazed to a radiator/condenser tube header 605 according to the prior art. As shown, the pin 600 is brazed onto the header 605 only on the outside edge of the header 605. The pin 600 is not brazed at the top of the header 605. Accordingly, the pin 600 is susceptible to becoming detached from the header 605 because only one surface of the header 605 is brazed to the pin 600.
Accordingly, plastic radiator/condenser pin assemblies are deficient because those made of a plastic resin make recycling more difficult and are insufficiently strong for heavy radiator/condenser assemblies and cannot also be used as an end cap. Solid metal pins are deficient because they are expensive, heavy, more difficult to machine and braze, cannot be used with a clad material, and cannot also be used as an end cap, without additional components or extensive part processing.